Photovoltaic panels, more commonly known as solar panels, are attractive methods of generating clean, renewable energy, and are particularly useful in remote or underserved areas where grid-supplied power is not readily available. Solar panels convert solar energy into electrical energy that can be used to power appliances, charge batteries, and perform other useful tasks. Various environmental conditions affect the efficiency and power production capabilities of a solar panel, however. The amount of power that a solar panel can generate depends, for example, on the temperature of the solar panel, the amount and/or brightness of the light incident on the solar panel, and the magnitude of the load(s) that are placed on the solar panel.
For a given operating condition of a solar panel (e.g., a given temperature and amount of incident light), there is an optimal set of load characteristics that will result in a maximum power output of the solar panel. Thus, in order to achieve the maximum amount of power from a solar panel for a given condition, certain electrical characteristics of the load (e.g., the impedance and/or resistance experienced by the solar panel) must be kept at the optimal value. However, operating conditions for a solar panel can change from day to day, and even from minute to minute. Accordingly, techniques for tracking the maximum power point of a solar panel, for example maximum power point tracking (MPPT) techniques, have been developed. But MPPT techniques are not all equally effective for all possible conditions. For example, a MPPT technique that works well for bright sunlight conditions may not work as well for heavily overcast conditions. Thus, even when using MPPT techniques, the full power generation capabilities of a solar panel may not be achieved across the full range of environmental conditions in which the solar panel operates.